This invention relates to a process for preparing primary aminoorganosilanes. More particularly, the present invention relates to a process for preparing a primary aminoorganosilane by the catalyzed reaction of a cyanoorganosilane with hydrogen.
A process of the foregoing type is described in U.S. Pat. No. 5,117,024. In accordance with this process, a cyanoorganosilane is reacted with hydrogen gas in the presence of a supported cobalt catalyst at a temperature of from about 100EC to 200EC and a pressure within a range of from about 200 psig to 2000 psig. The process is said to provide near quantitative selectivity for the desired primary aminoorganosilane without the production of hydrogen chloride and without the addition of ammonia and solvent systems as in then prior known processes.
A significant disadvantage to the process for making primary aminoorganosilanes described in U.S. Pat. No. 5,117,024 lies in its use of a supported cobalt catalyst. Such a catalyst is typically supplied in the passivated state, i.e., the cobalt particles are covered with a layer of oxide, in order to reduce the hazard of spontaneous combustion of the metal in an oxygen-containing environment such as air. Before the catalyst can be used, it must be activated, generally by reduction with hydrogen at fairly high temperatures, e.g., 500EC and even higher.